Combined triangle and protractor



UNITED. STATES PATENT OF ICE.

WARREN J. BEllCliER, OF

HARTFORD, CONNECTICUT.

SPECIFICATION To 11.1.4 whom it may cancer/1,:

angle and Protractor, of which the following is a specification.

This invent'on relates to combinationtools more particularlydesignated as a combined triangle and protractor, the object being to provide the ordinary draftsmans triangle with a protractor, whereby the instrument can not only be used in the usual way, but can also be used as a protractorfor obtaining difierent angles.

A further object of the invention is to pro vide a combined, tool of this character which will be simple in its construction and manipulation and apcurate in its measurements.

In the drawings accompanying and forming part of this specification, Figure 1 is an elevation of this improved combined tool, a part thereof being shown in section. Fig. 2 is a sectional view taken in line 2 2, Fig. 1; and Fig. 3 is a View of the member or spring for retaining the protractor in position.

Similar characters designate like parts in all the figures of the drawings.

As a preface'to a description of this improved combined tool it will be understood that the triangle can be made of any suitable material and in any desired way. It is, however, preferably made of celluloid or some suitable transparent material, whereby the graduations need be placed only on oneside thereof, and thus permit both sides of the tool to be utilized. It will also be further understood that while this particular construction of protractor, and the means for securing the same in position, is shown in I j connection with atriangle it may also be used a in connection with other tools and placed in position relatively thereto in the same-way.

- This improved combined tool comprises,'in'

a general 3 'ay, a triangle, a protractor secured thereto for adj nstment, and a spring for firmly holding the protractor in position and retaining the same throughout its adjustment.

in the preferred formthereof herein shown and described the triangle, which, as before stated, may be of any suitable construction forming part of Letters Patent No. 570,977, dated November 10, 1896. Application filed Au er-5,1896. serial No. 601,741. on nodal and material, has a circular opening 5, of .a size adapted for the purpose, intermediate its three plane faces (3, 7, and 8, and which circular opening 5 has a groove 9 in the edge of the triangle-frame bounding said opening, and which groove may be of any suitable shape, but is herein shown/preferably concaved. Disposed for adjustment within this opening and occupying substantialy one-half of the same is a protractor comprising a semicircular member or protractor-bar 10, connected at its ends by a cross member or bar 12, and which protracto'r-bar 10 has its outer edge 13 shaped to fit the groove 9 of the circular opening, and, as herein shown, is preferabl y convex or curved for this purpose. Asa means; for holding this protractor in position firmly and also for permitting the desired adjustment thereof a spring is used in connection therewith, and is herein shown in the natnreof a bow-spring 1- preferably of wire and of\a shape adapted to rest within the groove 9 and extend substantially around the'other half (at said opening 5, its ends 15 fitting within recesses 16 01 the cross-bar 12 of the protractor', and which recesses are contiguous to the holding-groove 9, whereby said protraetor will. be held at all times firmly against displacement, but will at the same time be capable of quick and perfect adj ustment.

The protractor-bar in any desired way, preferably ter or index-mark O" n p to 90, each main mark indicating ten degrees, and which-tendegree intervals are further divided intermediate thereof to indicate five degrees.

The triangle at one portion thereof, as 17, is marked with an index-mark OK to correspond with the index-mark O of thu p retractor-bar, and is also marked at each side of such indexmark 0 with graduations 18, reading from .0 to 5, whereby the protractor can not only be adjusted to indicate angles as low as five or ten degrees, but can also be adjusted to indicate angles of one degree.

On the triangle at each side of the one-degree graduations 18 are disposed a second series of graduations, as 19, for the purpose of securing adjustments equal to a half-dc.- gree, these marks 1'.) being disposed-at odd 10 might be graduated but it is herein shown graduated at both sides of its een-.

distances from the graduations 18.that is to say, as herein shown, the first graduationmark, as 2,0, of each series 19 is disposed at a distance equal to four and one-half degrees from the graduations 18, whereby they will indicate adjustments of the protractor equal to a half-degree in the'nlanner hereinafter set forth. It will be understoodthatother graduation-marks might be used to indicate adjustments of less than one-half degree by disposing them in substantially the same way. I In the use of this improved combined triangle and protractor, when it is desired to. ad ust the protractor to measure any desired angle, it is simply necessary to turn the same within the circular opening 5, to thereby bring the desired graduated mark of the protraotor- "bar adjacent to the index-mark 0 of the .trianglethat is to say, presuming it is desired to measure an angle of twenty-five degrees, as indicated in the drawings, it is simply necessary to bring the intermediate mark, as 21, located between the graduated marks 20 and of theprotractor-bar into line with the index-mark O of the triangle. If it is desired, however, to secure anadj ustme-nt equal'to an angle of twenty-six degrees, 4 it IS simply necessary to move the protractor to bring the mark 21 in line with the first graduation-mark, as 22, at one side of the index-mark 0 on the triangle. If it is de sired to secure an adjustment equal to an angle of twenty-six and. one-half degrees, it is simply necessary to bring the mark 21 into line with-the first graduated mark, as

' 29, at one ide of the index-mark 0" of the triangle, and then further more the protractor to either bring the marl: '28 intermediate the graduated marks 1O and 2O orthe mark 2 L intermediate thegraduated marks 30 and 40 into line with one of the graduated inarlgs 19 of either series of half-degree marks, whereby the protraetor will" indicate an angle of twenty-six and onedevice the necessity of forming on protractors a large number of graduations, as has heretofore been found necessary, is obviated.

This combined tool, it will be seen, can be used as a triangle or as a protractor or as a combined triangle and protractor. It will also be understood that the cross-bar 12 of.

the protractor can be used for sectional lining at any desired angle by simply adjusting the protractor to any desired position and then moving'thecombined tool in the usual way to secure the sectional lines. Thus the instrument forms a combined tool which is extremely simpl'ein its construction, effective in use, and inexpensive to manufacture, and which latter advantage is quite a material the edge t the adjustment thereof and securin g it firmly in such adjusted position against movement. It will be further-seen that such spring taxes up the wear resultant from the adjustment of the protractor and always holds the samein proper position relatively to its holdinggroove.

It will, furthermore, be understood that the graduated marks 18 and 19' need-not necessarily be placed directly on the triangle, as they might be placed on a supplemental member secured thereto eitherfor or without adj ustment. I

Having described my invention, I claim 1. The'combinationwith a triangle havinga circular opening the wall of which is. grooved throughout its entire circumference, of a semicircular protractor having a cross-bar recessed at each end; and a loose bow-spring fitted into, the unoccupied part of said opening and having its ends engaging the recesses of said cross-bar, said spring being movable with the protraetor and serving tohold the same inits adjusted position. 2. A supportin gframe having a completelyi nc losed circular opening provided with a grooved wall; a .protractor having aconvex edge disposed'in said opening andmovable entirely arennd the same; and a spring loosely engaging t" e protractor and movable therewith, lsr. ing serviugto hold the protracto-r in position. I

A supnortingame having an inclosed circular ope pievid-d with a groove in of bouniiing said opening; a

protractor having a part thereof shaped to fit said groove; and a spring fitting into the urn occupied portion of said groove and operable to hold the protractor in position.

4.. A triangle having an inelosed circular opening having a groove in the edge thereof bounding said opening; a protractor having a semicircular protractor-bar with its outer ed ge shaped to fitwithin said groove; and a bow-sprin g also fitting in the unoccupied portion of said groove and having its ends engaging said protractor, said. spring being adjustable simultaneously with the protractor entirely around the opening.

5. A triangle having a circular opening and bounding said opening; a protralctor having a semicircular member with lts outer edge shaped to fit into a part of'said groove; and

a bow-sprin g fittingin the unoccupied part of said groove and having its ends engaging the ends of the protractor for holding the same in position. r I

' WARREN J. nELoIIER.

\Vitnesses;v v

HENRY BISSELL,

FRED. J. DOLE.

provided with a groovein .the edge thereof 

